When performing cutting operations on materials like concrete, stone, and ceramics, dust is generated. This dust dirties the work area, can make it difficult to see the area being cut, and it could in special cases even be dangerous to inhale the dust in view of the risk of developing silicosis. Even the use of a mask is generally not sufficient to prevent the inhalation of the dust. Therefore, it has been suggested to direct a fog-like flow of water droplets against the working area for moistening dust particles that are generated during cutting, so as to reduce the quantity of dust. An example of a spray tool is a spray lid with integrated battery/batteries to be arranged on top of a standard 5 gallon cylindrical bucket. It is supplied by SMK Industries. To suck the liquid up from below a self priming pump of membrane type is used having a pressure of 1,8-2,8 bar. This type of pump requires a lot of energy and will therefore drain battery/ies quickly, thereby requiring frequent exchange of battery/ies. Further it is sensitive to particles/dirt in the fluid, that could easily clog the pump, especially its checkvalves.
It has been suggested to use a water tank, in which the pressure is pumped up manually, vide catalog 2008—Husqvarna Construction Products, p. 185, for example. Such a tank may be in the shape of an upright cylinder and usually is heavy and easy to turn over, so that the discharge hose will provide pressurized air instead of water. In addition, the manual pressurization of the tank will result in a quick reduction of the pressure and flow as the water level goes down. Therefore you must pump often, which interrupts your work.
Another suggestion is disclosed in U.S. Pat. No. 6,450,869 B1, which relates to an attachment for a hand cutting tool having at least one rotating blade. The attachment includes a portable device attachable to the hand cutting tool for producing a fog-like spray of water droplets near the rotating blade for moistening dust particles generated during cutting. Preferably, the attachment includes a portable source of pressurized water which can be carried like a back-pack on the body of a user holding the cutting tool, and at least one nozzle mounted in the blade guard and coupled to the source of pressurized water for producing a fog-like spray of water droplets. The source of pressurized water includes a small water container coupled to a pressurizing pump, which preferably should give a pressure of 260 kPa to achieve the desired fog-like spray of fine droplets, and which may be mounted in an electrical box that also includes an earth leakage switch. A voltage of 220 V is fed through the earth leakage switch to the machine and through its on/off-switch back to the pump. The combination inside a box of 220 V and a water pump may make a user feel unsafe, and in construction sites, 200 V is not always available, apart from often being timeconsuming to connect to the mains supply.
In US 2007/0246583 A1 there is disclosed a cutting device arrangement including a generator and a spray device in the region of a cutting tool, whereby liquid is sprayed for binding cutting residue blown up during the cutting process. The generator is driven by the engine of the device. The cutting device also includes a liquid supply device, such as a water tank or container, by means of which the liquid can be supplied to the spray device. An electric pump is provided as part of the spray device, so that the liquid can be sprayed under pressure, and the electric pump is operatively connected to the generator. The pump may be mounted to the bottom end of the tank, or in a hose from the tank to the cutting device, or even be integrated in the cutting device. In the first case, the pump is damaged easily due to its exposed location. In the second case both the pump and the electrical connection to the generator are susceptible to damage, and in the third case, the pump is protected, but the solution is expensive, since each device has to have a pump of its own.